Blender plane effect from blender render to cycles render
I think it's better not to give up to ready to use tools but just once learn how the transparency work in cycles, and then just use the knowledge.

https://www.youtube.com/results?search_query=transparent+textures+in+cycles

It's fairly easy. All you need is your png image's Alpha output as a mix node Factor to mix your image color in a Diffuse shader and a Transparent shader.